There's a little known researcher who is trying to expose evidence in support of a theory that in all likelihood most cases of actual intersex and transgender have been caused by the administration of heavy doses of synthetic hormones during pregnancy.
Here's a petition he started that explains his findings pretty well:
https://www.change.org/p/the-us-food-and-drug-administration-fda-acknowledge-that-hormone-treatment-during-pregnancy-can-cause-intersex-and-transgenderBased on what I've seen of the effects of DES, I think it's quite likely that the whole transgender phenomenon of recent times is largely being driven by people who were exposed to DES or other female hormone derivatives before birth.
Although DES was withdrawn from use 40 years ago, other treatments involving high doses of other female hormone derivatives are still in use. One example is "Proluton Depot", an injectible progestin (the same type of synthetic hormone as is used to chemically castrate sex offenders!). The standard dose for prevention of miscarriage or premature birth is either 250mg or 500mg a week, which if you know anything about hormones, looks like a very high dose indeed.
He's posted further research and articles about it on the site HormoneMatters:
https://www.hormonesmatter.com/author/hugh-easton/More people need to know about this so it will lead to awareness and stopping the administration of such hormones during pregnancy.
